The pilot reported that he was returning to a newly graded hard black soil strip at a muster camp. As the aircraft was turned at the end of the landing roll the nosewheel entered a pothole, causing the nosewheel yoke to break. The nose of the aircraft dropped and the tips of the propeller were bent on contact with the strip surface. This accident was not the subject of an on-site investigation.

The pilot was carrying out circuits and landings. Following a touch-and-go landing, the pilot had just reduced power at about 200 feet above ground level when the engine failed completely. The pilot turned the aircraft back towards the runway. After completing the turn, he realised he was too high and fast, with a 15 knot tailwind, to land on the runway. Sighting a paddock to his left, he made another turn back into wind toward it. The aircraft sank heavily onto the ground inside the aerodrome boundary, ran through a fence, and bounced back into the air. It then passed underneath a set of power lines, floated across the New England Highway and a second fence, and landed in the paddock, coming to rest some 365 metres from the initial touchdown marks. No fault was found with the aircraft engine or systems. The aircraft had carried sufficient but minimum fuel for the flight and it was considered that during manouevring a tank outlet may have become uncovered, resulting in fuel starvation to the engine.

On the first approach to land the aircraft was caught by a wind gust and the pilot carried out a go around. On the second approach the aircraft touched down and bounced. On the subsequent touchdown the aircraft was struck by another gust the left wing lifted and the aircraft tipped onto its nose and right wingtip. It then fell back onto its wheels veered to the left and ran off the runway. The wind strength at the time was reported as being 15 to 20 knots with gusts. The crosswind on the runway in use averaged 18 knots with a maximum of 25 knots. Local terrain features also caused variable wind problems. The into-wind runway was not available as it was being used for aircraft parking for visitors to an air show. The maximum crosswind component for the aircraft type was listed as 15 knots. The pilot was relatively inexperienced and had not previously landed in similar wind conditions.

During the takeoff roll, witness evidence suggested that the right mainwheel tyre had blown. The pilot requested a low pass for an inspection of the gear and it was determined that the complete right mainwheel was missing. After reducing fuel weight to a minimum by burnoff, the pilot carried out a wheels-up landing on the runway which had been foamed in advance. Subsequent on-site inspection by the Civil Aviation Authority airworthiness staff determined that four adjacent mainwheel tie bolts had failed due to under-torquing. The resulting play in the wheel halves then caused the mainwheel bearing to fail followed by the stripping of the remaining tie bolt nuts and the complete separation of the outer half of the mainwheel and the tyre. The last periodic inspection of the aircraft was completed just prior to the accident flight.

The pilot stated that he allowed the engine temperature to stabilise for about two minutes at 2800 RPM after landing, then reduced power to about 2000 RPM for a further minute. At about the same time a severe bouncing started, the pilot disengaged the rotors and attempted to shut the engine down. The helicopter was affected by ground resonance and the pilot, who had already released his seat belt, was thrown to the floor of the helicopter.

While flying straight and level at 45 knots, the engine began to splutter. The pilot immediately used the hand fuel pump but his efforts were unsuccessful and the engine stopped as a result of fuel starvation. From the air the ground below looked suitable for a forced landing. However, at a low height it became apparent that the ground surface was rocky. During the landing roll the left mainwheel struck a rock. A subsequent examination of the fuel system discovered a piece of red, electrical, insulation tape within the fuel tank. This tape had blocked off the outlet pipe from the fuel tank to the engine. The pilot believes that the piece of electrical tape had probably originated from refuelling equipment and entered the tank during a refuel from drum stock.

A pilot who is based at Lake Evella was on scene soon after the accident occurred. He located the pilot-in-command who conveyed the following sequence of events. The takeoff was commenced from the threshold of the strip. The aircraft was being flown by the pilot under instruction. It lifted off further down the strip than the instructor expected, then commenced climbing at 80 knots. Very shortly after lift off the engine suffered a partial power loss. The instructor took control of the aircraft and checked fuel contents and saw that the mixture was rich. He then closed the throttle because he realized that he would have to land the aircraft on the remaining runway and overrun area and lowered full flap. He then assessed that he could not land in the available cleared area ahead so he turned right into wind and looked for a cleared area to land. The aircraft then flew into trees, striking several large trees before impacting with the ground at a low speed. The instructor said that he and probably the surviving passenger were thrown clear of the aircraft during the impact sequence, however, both were badly burned. The investigation focussed on trying to determine the reason for the engine malfunction. One possibility considered was that the take-off was commenced with the fuel selector in the OFF position. This was considered a possibility because the student pilot was trained overseas and may have been trained to switch the fuel selector off during the shutdown checks. The operator's normal procedure was to leave the fuel selector ON after engine shutdown. Another possibility was that the instructor may have turned the selector to the OFF position in order to check the thoroughness of the students pre-start checks. The fuel selector was badly damaged by fire, but it was determined that the selector, although displaced slightly from the BOTH position, was in a position where the fuel supply to the engine would not have been interrupted. A trial was made using the same model aircraft, in order to estimate how far into the take off run the aircraft would get if the engine was started with the fuel selector in the OFF position. The engine failed due to fuel starvation after one minute five seconds idling at 1000 RPM. It was considered that due to the distance of the tarmac area from the threshold of the runway used for DEPARTURE, the engine would have stopped before the take-off could have commenced. Therefore the hypothesis that the take-off was commenced with the fuel selector in the OFF position has been discounted. The engine was dismantled and examined in order to determine pre-impact serviceability. No defect that could have caused either a partial or complete engine failure was discovered. However, the investigation was impeded by the extensive post impact fire damage to the components of the engine. Parts of the air induction system and carburettor were destroyed, although some testing was possible. The magnetos were damaged to the extent that meaningful examination was impossible. Therefore a malfunction of one of the vital components of the engine cannot be discounted. The loss of power occurred when the aircraft was approximately 100 feet above ground level. From such a height it is not possible to turn back and land on the runway and in this case there was insufficient runway ahead to land. The strip is surrounded by trees which meant that there was no suitable area for a forced landing within gliding distance.

The pilot reported that as the aircraft climbed through about 300 feet after takeoff, the engine RPM suddenly dropped by 350-400. This was accompanied by rough running. The pilot decided to land in a gravel pit just beyond the airfield boundary. The aircraft was stopped after a ground run of 150 metres but received substantial damage due to the rough surface. The engine problem was probably caused by sticking valve(s). This accident was not the subject of an on-site investigation.

Circumstances:

The aircraft was on a flight from Port Macquarie, NSW to Moorabbin, VIC with an intermediate stop at Wangaratta, VIC. When nine kilometres north-east of Moorabbin, at an altitude of about 2500 feet, the engine stopped without warning. The pilot was unable to restart the engine in the time available and forced landed the aircraft onto a road. The left wing was substantially damaged when it collided with roadside obstructions. Investigation showed water was present in the right wing fuel collector tank, the fuel pump, the fuel control unit and in the fuel manifold valve. The aircraft was found to have had a history of water ingress into the fuel system. The wing upper access panels had previously been removed and resealed, and the fuel filler caps had been replaced. The pilot had fully refuelled the aircraft two days prior to the accident and during those two days torrential rain fell at the Port Macquarie airfield where the aircraft was parked. On the morning of the accident the pilot reported that he did not find any water when he checked the fuel system drains. The latter part of the flight had been through moderate to severe turbulence and it is suspected that water sitting within the wing fuel tank had been agitated and found its way into the engine supply system. It was not determined how the water entered the wing fuel tank, however, it is possible that some water had been present prior to the tank resealing, some weeks prior to the accident, and some may have entered the tank during the two days prior to this flight. At the accident site the left fuel tank was found to contain 53 litres of fuel while the right tank was virtually empty. Based on calculations of flight time versus known fuel consumption rates, there should have been about 117 litres of fuel remaining in the fuel tanks. The cause of the loss of fuel was not established. However, the pilot has advised that fuel has been stolen from aircraft based at Port Macquarie. Because the aircraft had not been flown since the pilot refuelled it, he did not visually check the tank contents prior to DEPARTURE from Port Macquarie. Although all the fuel could not be accounted for and the right tank was near empty, these facts were not considered factors in the accident. During his attempt to restart the engine, the pilot did not follow the procedure specified in the Pilot's Operating Handbook in that the throttle was fully open, the electric fuel pump was on, and the mixture rich. This would have severely limited the chances of a successful restart. (The throttle should have been half open, the electric fuel pump off and the mixture lean.) After a basic examination of the aircraft at the accident site, the engine was started without any problem.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. The engine lost power due to water contamination of the fuel system.

2. The pilot did not use the correct procedure to attempt to restart the engine.

3. The pilot's attempt to restart the engine was not successful.

4. The pilot was forced to land on an obstructed roadway.

5. It is likely that the turbulence flown through during the latter stages of the flight caused the water in the fuel system to enter the engine.

The helicopter was carrying 360 litres of water based Herbicide and about 90 litres of fuel when it took off the second time that morning. Flying activity had commenced later than planned due to local fog and low cloud in the area to be sprayed. A level area on the bank of the creek was used for loading and the pilot availed himself of the open space over the creek to accelerate before commencing a climb out to the treatment area. This technique involved an immediate loss of ground effect as the helicopter moved off the elevated creek bank. The aircraft failed to achieve translational flight and the pilot "sensed" a power loss as it descended towards the fast flowing creek. The left skid fractured when it struck a log protruding from a low island. The impact rotated the helicopter through 180 degrees causing the pilot to lose sight of the only reasonable landing area on the opposite bank. The helicopter settled and balanced on sloping ground whilst the engine wound down due to fuel starvation caused by a fuel feed line separation in the initial impact. As the rotor system slowed down, the helicopter fell onto its damaged left side. The pilot was using a pad that was not suitable for the operation. The pad was limited by a fence line at one side which was high enough to prevent operations over it at high all up weights and a creek at the other side which caused an immediate loss of ground effect as soon as the helicopter moved off the pad. Trees and high terrain prevented other take-off options. The pilot was using the potential energy of pad height above the creek to gain airspeed quickly and early translational flight. On this occasion he did not obtain translational flight and the helicopter descended into the creek. The pilot overpitched the main rotor blades causing a loss of RPM and power. The engine and fuel components were examined in detail and no mechanical reason for a power loss was discovered. The helicopter was fitted with a spray system that was not authorised for the type in Australia, the performance combination of helicopter and spray system was unknown.